Exhaust systems in modern vehicles are configured to fit relatively close to the passenger compartment of a vehicle and in many cases bisect the car body from front to rear resulting in a hump extending the length of the passenger compartment. The passenger compartment side of the hump is carpeted with decorative material. Because of the close proximity of the exhaust system to the carpeting, the heat of the exhaust system tends to cook, discolor and eventually destroy the carpet near to the hump unless a shield is applied to the vehicle intermediate the carpet and the exhaust system.
U.S. Pat. No. 3,677,365 discloses a shield system mounted to the underside of a vehicle where the shield system completely surrounds the exhaust system. One of the objects of the 1972 patent is to retain heat in the exhaust system.
U.S. Pat. No. 3,698,440 discloses an insulation system to completely surround a conduit transporting hot liquid or gaseous material. The system includes a plurality of layers, namely, a heat insulating material of rigid polyurethane foam between a pair of corrugated metal sheaths.
U.S. Pat. No. 4,315,558 discloses an exhaust system having a mesh shield around a longitudinally expandable exhaust system. The exhaust system is mounted to the body of the vehicle by a series of springs placed along its length.
U.S. Pat. No. 4,993,512 discloses a vehicle exhaust system confined within a casing which casing is mounted to the vehicle body. The casing completely encloses the exhaust system to retain heat.